Blackpoll Warbler

Identificazione

The blackpoll warbler is a fairly small bird which attains the weight of a ballpoint pen.: 65  However, it is one of the larger of the diverse genus Setophaga (formerly Dendroica). In the species, body length can vary from 12.5 to 15 cm (4.9 to 5.9 in) and wingspan can range from 20 to 25 cm (7.9 to 9.8 in). Body mass can vary from 9.7 to 21 g (0.34 to 0.74 oz), with an average bird anywhere between 12 and 15 g (0.42 and 0.53 oz). Among standard measurements, the wing chord is 6.6 to 8 cm (2.6 to 3.1 in), the tail is 4.5 to 5.4 cm (1.8 to 2.1 in), the bill is 0.8 to 1.2 cm (0.31 to 0.47 in) and the tarsus is 1.8 to 2 cm (0.71 to 0.79 in). The summer male blackpoll warblers have dark-streaked brown backs, white faces, and black crowns. Their underparts are white with black streaks, and they display two white wing bars. The adult females essentially resemble washed-out versions of the summer males, and in particular, the females lack the strong head patterns, and their crowns and faces are shades of gray. Another outstanding physical characteristic of the species is the bright orangish-pink legs.<p>Non-breeding birds of this species have greenish heads, dark-streaked greenish upperparts, and yellowish breasts, with the yellow extending to the belly in young birds. Their wing bars are always present.

Tassonomia

Genere: Setophaga; famiglia: Parulidae; ordine: Passeriformes.

Nome scientifico

Setophaga striata

Autorità

(Forster, JR, 1772)

Ordine

Passeriformi

Famiglia

Parulidae

Genere

Setophaga

Areale e habitat

In the southern portion of their breeding range, blackpoll warblers can be found on the higher elevations of mountains in woodland or brushy areas. They also spend their summers on the wooded coastal islands of Maine and the Maritime Provinces. Farther north, they have been reported throughout the boreal coniferous forest. Blackpolls breed nearer to the tundra than any other warbler.

Areale riproduttivo

NA : Alaska to e, se Canada and ne USA

Areale non riproduttivo

America meridionale settentrionale e centrale

Migrazione

Migratori completi

Comportamento

Comportamento migratorio: Migratori completi.

Conservazione

Tendenza della popolazione: in diminuzione.

Tendenza della popolazione

in diminuzione